In the packaging of butter, margarine, soft cheese, and the like it is necessary that the viscous mass be loaded as quickly as possible into the containers it is to be packaged in. If the mass is allowed to stand it quickly hardens; indeed some types of margarine can solidify in a period of several seconds if left quiescent.
A known device has a filling funnel or hopper into which the viscous mass is poured from a producing machine. At the bottom of the hopper one or more dosing valves is provided to pull off predetermined quantities of the mass and eject it from the funnel into a container. The operation is carried out as fast as possible in order to prevent the material from settling and hardening in the hopper. In addition extremely careful design of the hopper is necessary in order to prevent dead corners or the like in the apparatus from filling up with hardened material.
Typically in such a device it is known to provide a pair of valve sleeves which have at one side a valve port that can be turned either toward the interior filling funnel or toward the container to be filled. Each of these valve sleeves has a respective piston and the two pistons are linked together, as well as the two valves so that they have simultaneous intake strokes which draw a quantity of the mass out of the funnel, and then both of the sleeves are turned over and the pistons are advanced so as to eject both of these quantities from the tubes into respective containers. Although such a system operates relatively rapidly it still has the disadvantage that between strokes of the pistons the material has a chance to settle and, therefore, harden. In addition any breakdown along the production line can cause the entire batch to be lost, or at least require it to be scooped out of the funnel and replaced in the processing device.